Babbage, Charles (1791–1871)

Babbage and a working Difference Engine built at the Science Museum, London.

"On two occasions I have been asked [by members
of Parliament], "Pray, Mr. Babbage, if you put into the machine wrong
figures, will the right answers come out?" I am not able rightly to
apprehend the kind of confusion of ideas that could provoke such a question." – Charles Babbage

Charles Babbage was an English mathematician and inventor who served as Lucasian Professor of Mathematics
at Cambridge (1828–1839) and became the most important figure in the
prehistory of computers. Babbage noted
that astronomical and other mathematical tables of the period were riddled
with errors because all the calculations had to be done by hand. This gave
him the idea of building a machine that would do the tedious work of computation
more accurately, faster, and without ever getting tired.

Born at Totnes, Devonshire, Babbage entered Trinity College, Cambridge,
in 1811, but graduated from Peterhouse in 1814. Two years later he was elected
a Fellow of the Royal Society. The idea of building a calculating machine
first occurred to him in 1812.

The Difference Engine
and beyond

In 1822, Babbage wrote a letter to one of the top British scientists of
the day, Humphry Davy, in which he talked about
the design of an automatic calculator. Shortly after, he was given a grant
by the British Government to build this device – an elaborate symphony
of rods and interlocking gear teeth – which Babbage called the Difference
Engine. Construction started but never finished. Despite heroic efforts
to construct a working model, the critical tolerances were beyond what engineers
could provide in the first half of the 18th century (though the gear-making
skills learned gave Britain an edge in precision machinery for several decades
and even contributed to the qualitative superiority of the British navy
in World War I). The government had spent £17,000, and Babbage £6,000 his
own money, on the project, when Babbage set his sights on something even
more ambitious. He grasped that the basic mechanisms of the Difference Engine
could be generalized to an all-purpose calculating machine, programmable
by a punched-card mechanism like that of a Jacquard loom. This vastly more
powerful machine was called the Analytical Engine and would have been the
world's first true computer. But it never got off the ground. "He was ill-judged
enough," wrote the secretary of the Royal Astronomical Society, "to press
the consideration of this new machine upon the members of Government, who
were already sick of the old one." Prime Minister Robert Peel was less than
enthusiastic: "I would like a little previous consideration before I move
in a thin house of country gentlemen a large vote for the creation of a
wooden man to calculate tables from the formula x2 + x + 41."

The government's eventual withdrawal of support for his schemes left Babbage
a disappointed and embittered man. However, his ideas survived and proved
to be the forerunner of modern computers. Parts of his uncompleted mechanisms
are on display in the London Science Museum. In 1991, working from Babbage's
original plans, a Difference Engine was completed – and functioned
perfectly.

Other achievements

Babbage played a part, along with John Herschel and G. Peacock, in introducing the Leibnizian (see Leibniz)
"d" notation for calculus into British
mathematical use in place of the less flexible "dot" notation devised by Newton.

Among Babbage's many less famous accomplishments was his cracking of the
Vigenère Cipher, a discovery that helped English military campaigns
but wasn't published for several years by which time the credit had gone
instead to Friedrich Kasiski, who broke the code some years after Babbage.

In his later years Babbage became fiercely and eccentrically hostile to
organ-grinders, in spite of whom he survived until October 18, 1871.

Reference

1. Swade, Doron. The Difference Engine: Charles Babbage and the Quest
to Build the First Computer. New York: Viking, 2000.